Farmers in Brazil are more likely to invade each others' land in years that are particularly wet or unusually dry. Americans honk their horns more at other
cars when it's hot outside. Countries in the tropics are more likely to have civil wars in years that are especially hot or dry.

They may seem random, but actually, these events are all connected. New research from Princeton University and UC Berkeley published today in Science reveals a link between big shifts in climate and precipitation and a rise in interpersonal violence, institutional breakdown, and especially inter-group
violence, such as war. Not only does the paper shed light on past bouts of global conflict, it also offers a warning about the future. The world is
expected to warm by at least 2 degrees Celsius over the next few decades, unless governments do something drastic, and the researchers say that increased
bloodshed could be a serious side-effect of that trend.

For this study, the researchers performed a meta-analysis of 60 studies, some of which contained data going back to 10,000 B.C. They found that as
temperature increases one standard deviation from the mean -- roughly equivalent to warming a U.S. county by 5 degrees Fahrenheit in a given month -- the
likelihood of interpersonal violence rises by 4 percent and that of intergroup conflict rises by 14 percent.

The results touch on nearly every world region and hold true for both periods of extreme warming and cooling. Even the collapse of the Mayan civilization
and major dynastic transitions in ancient China were preceded by drought and extreme weather. During the Little Ice Age, which started at around 1550,
European countries were much more likely to go to war with each other.

Solomon Hsiang, a public policy professor at Princeton and one of the study's lead authors, told me that while his team did discover that conflict and
climate change are related, they still don't know why it is that temperature change makes us so belligerent. And, more importantly, they aren't saying
climate change is the only or even primary cause of violence.

"We're in the position medical researchers were in in the 1930s," he told me. "Smoking was the clear proximate cause of lung cancer, but it wasn't until
decades later that we understood how that was linked."

They do offer a few theories, though. Climate change causes migration, and as big populations move, they might confront existing residents in a battle for
resources and land. It can also alter physical environments in a way that predisposes people to confrontation, or -- particularly in earlier eras -- might
have caused people to wrongly attribute environmental conditions to the actions of their enemies. Other studies have shown that hot temperatures make us more hostile
psychologically.

Changes in the environment can also cause labor productivity to decline, which is what happened with our earlier example of civil war in the tropics:
There's less farm work during a drought, so there are more unemployed people. So if you're looking to build an army and overthrow a government, it's easier
to do it when there are a lot of idle, would-be farm workers around, complete with pitchforks.

Some unrelated studies have shown that armed conflict has globally declined over the past 50
years or so, even though the world has been warming the entire time. Hsiang pointed out that it's important to remember that he's looking at what would have happened had there been no climate change during those decades -- and the answer, he says, is that rates of conflict would have fallen
even faster.

"By focusing only on one country at a time, all we are doing is comparing a country to itself as the population is responding to changes in its
environment," he said.

So what does this say about the present day? This is one of the few studies that points to climate change's likely impact on human society, as opposed to
things like melting ice caps and rising sea levels, but it also helps us think about how much we want to spend to mitigate global warming. If we add "less peace" to all of global warming's already horrific environmental impacts, it might change our calculus significantly.

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Writing used to be a solitary profession. How did it become so interminably social?

Whether we’re behind the podium or awaiting our turn, numbing our bottoms on the chill of metal foldout chairs or trying to work some life into our terror-stricken tongues, we introverts feel the pain of the public performance. This is because there are requirements to being a writer. Other than being a writer, I mean. Firstly, there’s the need to become part of the writing “community”, which compels every writer who craves self respect and success to attend community events, help to organize them, buzz over them, and—despite blitzed nerves and staggering bowels—present and perform at them. We get through it. We bully ourselves into it. We dose ourselves with beta blockers. We drink. We become our own worst enemies for a night of validation and participation.

Even when a dentist kills an adored lion, and everyone is furious, there’s loftier righteousness to be had.

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But Cecil fatigue is only going to get worse. On Friday morning, Zimbabwe’s environment minister, Oppah Muchinguri, called for the extradition of the man who killed him, the Minnesota dentist Walter Palmer. Muchinguri would like Palmer to be “held accountable for his illegal action”—paying a reported $50,000 to kill Cecil with an arrow after luring him away from protected land. And she’s far from alone in demanding accountability. This week, the Internet has served as a bastion of judgment and vigilante justice—just like usual, except that this was a perfect storm directed at a single person. It might be called an outrage singularity.

Forget credit hours—in a quest to cut costs, universities are simply asking students to prove their mastery of a subject.

MANCHESTER, Mich.—Had Daniella Kippnick followed in the footsteps of the hundreds of millions of students who have earned university degrees in the past millennium, she might be slumping in a lecture hall somewhere while a professor droned. But Kippnick has no course lectures. She has no courses to attend at all. No classroom, no college quad, no grades. Her university has no deadlines or tenure-track professors.

Instead, Kippnick makes her way through different subject matters on the way to a bachelor’s in accounting. When she feels she’s mastered a certain subject, she takes a test at home, where a proctor watches her from afar by monitoring her computer and watching her over a video feed. If she proves she’s competent—by getting the equivalent of a B—she passes and moves on to the next subject.

The Wall Street Journal’s eyebrow-raising story of how the presidential candidate and her husband accepted cash from UBS without any regard for the appearance of impropriety that it created.

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The piece begins by detailing how Clinton helped the global bank.

“A few weeks after Hillary Clinton was sworn in as secretary of state in early 2009, she was summoned to Geneva by her Swiss counterpart to discuss an urgent matter. The Internal Revenue Service was suing UBS AG to get the identities of Americans with secret accounts,” the newspaper reports. “If the case proceeded, Switzerland’s largest bank would face an impossible choice: Violate Swiss secrecy laws by handing over the names, or refuse and face criminal charges in U.S. federal court. Within months, Mrs. Clinton announced a tentative legal settlement—an unusual intervention by the top U.S. diplomat. UBS ultimately turned over information on 4,450 accounts, a fraction of the 52,000 sought by the IRS.”

There’s no way this man could be president, right? Just look at him: rumpled and scowling, bald pate topped by an entropic nimbus of white hair. Just listen to him: ranting, in his gravelly Brooklyn accent, about socialism. Socialism!

And yet here we are: In the biggest surprise of the race for the Democratic presidential nomination, this thoroughly implausible man, Bernie Sanders, is a sensation.

He is drawing enormous crowds—11,000 in Phoenix, 8,000 in Dallas, 2,500 in Council Bluffs, Iowa—the largest turnout of any candidate from any party in the first-to-vote primary state. He has raised $15 million in mostly small donations, to Hillary Clinton’s $45 million—and unlike her, he did it without holding a single fundraiser. Shocking the political establishment, it is Sanders—not Martin O’Malley, the fresh-faced former two-term governor of Maryland; not Joe Biden, the sitting vice president—to whom discontented Democratic voters looking for an alternative to Clinton have turned.

During the multi-country press tour for Mission Impossible: Rogue Nation, not even Jon Stewart has dared ask Tom Cruise about Scientology.

During the media blitz for Mission Impossible: Rogue Nation over the past two weeks, Tom Cruise has seemingly been everywhere. In London, he participated in a live interview at the British Film Institute with the presenter Alex Zane, the movie’s director, Christopher McQuarrie, and a handful of his fellow cast members. In New York, he faced off with Jimmy Fallon in a lip-sync battle on The Tonight Show and attended the Monday night premiere in Times Square. And, on Tuesday afternoon, the actor recorded an appearance on The Daily Show With Jon Stewart, where he discussed his exercise regimen, the importance of a healthy diet, and how he still has all his own hair at 53.

Stewart, who during his career has won two Peabody Awards for public service and the Orwell Award for “distinguished contribution to honesty and clarity in public language,” represented the most challenging interviewer Cruise has faced on the tour, during a challenging year for the actor. In April, HBO broadcast Alex Gibney’s documentary Going Clear, a film based on the book of the same title by Lawrence Wright exploring the Church of Scientology, of which Cruise is a high-profile member. The movie alleges, among other things, that the actor personally profited from slave labor (church members who were paid 40 cents an hour to outfit the star’s airplane hangar and motorcycle), and that his former girlfriend, the actress Nazanin Boniadi, was punished by the Church by being forced to do menial work after telling a friend about her relationship troubles with Cruise. For Cruise “not to address the allegations of abuse,” Gibney said in January, “seems to me palpably irresponsible.” But in The Daily Show interview, as with all of Cruise’s other appearances, Scientology wasn’t mentioned.

An attack on an American-funded military group epitomizes the Obama Administration’s logistical and strategic failures in the war-torn country.

Last week, the U.S. finally received some good news in Syria:.After months of prevarication, Turkey announced that the American military could launch airstrikes against Islamic State positions in Syria from its base in Incirlik. The development signaled that Turkey, a regional power, had at last agreed to join the fight against ISIS.

The announcement provided a dose of optimism in a conflict that has, in the last four years, killed over 200,000 and displaced millions more. Days later, however, the positive momentum screeched to a halt. Earlier this week, fighters from the al-Nusra Front, an Islamist group aligned with al-Qaeda, reportedly captured the commander of Division 30, a Syrian militia that receives U.S. funding and logistical support, in the countryside north of Aleppo. On Friday, the offensive escalated: Al-Nusra fighters attacked Division 30 headquarters, killing five and capturing others. According to Agence France Presse, the purpose of the attack was to obtain sophisticated weapons provided by the Americans.

The Islamic State is no mere collection of psychopaths. It is a religious group with carefully considered beliefs, among them that it is a key agent of the coming apocalypse. Here’s what that means for its strategy—and for how to stop it.

What is the Islamic State?

Where did it come from, and what are its intentions? The simplicity of these questions can be deceiving, and few Western leaders seem to know the answers. In December, The New York Times published confidential comments by Major General Michael K. Nagata, the Special Operations commander for the United States in the Middle East, admitting that he had hardly begun figuring out the Islamic State’s appeal. “We have not defeated the idea,” he said. “We do not even understand the idea.” In the past year, President Obama has referred to the Islamic State, variously, as “not Islamic” and as al-Qaeda’s “jayvee team,” statements that reflected confusion about the group, and may have contributed to significant strategic errors.

Some say the so-called sharing economy has gotten away from its central premise—sharing.

This past March, in an up-and-coming neighborhood of Portland, Maine, a group of residents rented a warehouse and opened a tool-lending library. The idea was to give locals access to everyday but expensive garage, kitchen, and landscaping tools—such as chainsaws, lawnmowers, wheelbarrows, a giant cider press, and soap molds—to save unnecessary expense as well as clutter in closets and tool sheds.

The residents had been inspired by similar tool-lending libraries across the country—in Columbus, Ohio; in Seattle, Washington; in Portland, Oregon. The ethos made sense to the Mainers. “We all have day jobs working to make a more sustainable world,” says Hazel Onsrud, one of the Maine Tool Library’s founders, who works in renewable energy. “I do not want to buy all of that stuff.”

A controversial treatment shows promise, especially for victims of trauma.

It’s straight out of a cartoon about hypnosis: A black-cloaked charlatan swings a pendulum in front of a patient, who dutifully watches and ping-pongs his eyes in turn. (This might be chased with the intonation, “You are getting sleeeeeepy...”)

Unlike most stereotypical images of mind alteration—“Psychiatric help, 5 cents” anyone?—this one is real. An obscure type of therapy known as EMDR, or Eye Movement Desensitization and Reprocessing, is gaining ground as a potential treatment for people who have experienced severe forms of trauma.

Here’s the idea: The person is told to focus on the troubling image or negative thought while simultaneously moving his or her eyes back and forth. To prompt this, the therapist might move his fingers from side to side, or he might use a tapping or waving of a wand. The patient is told to let her mind go blank and notice whatever sensations might come to mind. These steps are repeated throughout the session.